CN1550697A

CN1550697A - Control apparatus and method for lock-up clutch of vehicle

Info

Publication number: CN1550697A
Application number: CNA200410034794XA
Authority: CN
Inventors: 大岛康嗣; 木村弘道; 武内博明; ֮; 渡辺和之; 近藤贵裕; ־; 绫部笃志; 河村达哉; 佐川步; ��һ; 杉村敏夫; 奥田弘一
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2003-05-16
Filing date: 2004-05-17
Publication date: 2004-12-01
Also published as: JP2005003193A; US20040229728A1

Abstract

In a vehicle having a hydraulic power transmitting device equipped with a lock-up clutch on an output side of the engine, a control apparatus for controlling the lock-up clutch is provided which includes a lock-up clutch control unit that places the lock-up clutch in a slipping state when the vehicle is started so that torque received from the engine is transmitted to a later-stage transmission via the lock-up clutch as well as the hydraulic power transmitting device.

Description

Lock-up clutch of vehicle control apparatus and method

Invention field

The present invention relates generally to a kind of equipment and method of a lock-up clutch of control one vehicle, a part that is particularly related to a kind of torque that when vehicle launch one motor is generated is passed to the technology of grade speed changer after through a lock-up clutch and a dydraudynamic drive unit, thereby the fuel economy of guaranteeing vehicle is further enhanced.

Background technique

In a kind of known vehicles, use a dydraudynamic drive unit, this dydraudynamic drive unit comprises the lock-up clutch of the input and output rotating component of direct this device of coupling, and the input shaft of this automatic transmission is passed in the output torque of motor through this dydraudynamic drive unit that this lock-up clutch is housed.This dydraudynamic drive unit as a fluid coupling or a torque-converters be used in a pump impeller that is connected with motor and one with turbine that the input shaft of this automatic transmission is connected between fluid such as hydraulic fluid or hydraulic oil transmission power.For this vehicle that comprises the dydraudynamic drive unit that lock-up clutch is housed, people have proposed various measures and have improved fuel economy.For example, Japan Patent open No.5-141528 (JP-A-5-141528) has proposed one and has been used for a control gear that skids of lock-up clutch of vehicle that the dydraudynamic drive unit of a lock-up clutch is housed.When the driving conditions of the vehicle in the disclosure document be in prestor relation shown in Figure 7 according to JP-A-5-141528 from actual vehicle speed (output shaft rotating speed) thereby and be judged to be a certain vehicle low velocity zone that draws of closure opening θ th and a certain low accelerating region and be in one when skidding in the control zone, this control gear that skids is used for the local engagement lock-up clutch and promptly lock-up clutch is placed slipping state, thereby reduce the rotation loss of motor, improve fuel economy or efficient.

In the control gear that skids of known lock-up clutch as mentioned above, when vehicle stops for preventing engine stall (engine stall), lock-up clutch is in separated state usually, lock-up clutch also is in separated state when stationary vehicle is started, to improve the starting and the accelerating ability of engine speed and raising vehicle.When a torque-converters was used as dydraudynamic drive unit, torque-converters was used for amplifying torque in the one torque conversion range, thereby guarantees further to improve accelerating ability when vehicle launch.

But, in the control gear that skids of lock-up clutch as mentioned above, lock-up clutch separates usually during vehicle launch, so fuel efficiency is decided by torque capacity/torque capacity (torque capacity) of being determined by the specification of dydraudynamic drive unit during vehicle launch.Therefore, the fuel efficiency that provides of the known control gear that skids may not be enough high.For example, as transmitting torque greater than the torque capacity of dydraudynamic drive unit to this device from motor, then this torque just is used for improving engine speed, thereby the engine power waste causes fuel efficiency to descend.

Summary of the invention

Therefore an object of the present invention is to provide a kind of control apparatus of a lock-up clutch of a vehicle, this vehicle has a dydraudynamic drive unit that this lock-up clutch is housed at the outlet side of motor, and this lock-up clutch of this Equipment Control is to improve fuel economy or efficient.Another object of the present invention provides a kind of method of controlling this lock-up clutch of this vehicle.

For realizing above-mentioned and/or other purpose, according to a first aspect of the present invention, a kind of control apparatus of a lock-up clutch of control one vehicle is provided, this vehicle has a dydraudynamic drive unit that this lock-up clutch is housed, this dydraudynamic drive unit is arranged on the outlet side of the motor of this vehicle, and this equipment comprises that one places this lock-up clutch the lock-up clutch control apparatus/unit of slipping state when vehicle launch.

Use control apparatus as mentioned above, this lock-up clutch control apparatus places slipping state to lock-up clutch during vehicle launch, so the torque from motor output is passed to back grade (for example automatic transmission) through lock-up clutch and dydraudynamic drive unit a drive path during vehicle launch.Therefore, control apparatus of the present invention prevents when vehicle launch or suppresses engine speed otherwise possible excessive raising, thereby power only compares by the existing situation of dydraudynamic drive unit transmission during with vehicle launch, and fuel economy or efficient are improved when guaranteeing vehicle launch.

According to a second aspect of the present invention, a kind of control apparatus of a lock-up clutch of control one vehicle is provided, this vehicle comprises that (a) is equipped with direct coupling one input rotating component and the dydraudynamic drive unit of the lock-up clutch of an output rotating component and (b) one is operatively connected with this outlet side that dydraudynamic drive unit of this lock-up clutch is housed, the automatic transmission of the selected speed change level of one in a plurality of speed change levels is established in the combination of the working state by changing a plurality of hydraulic frictional devices, this equipment comprises that (1) one at least one hydraulic frictional device that when vehicle parking the hydraulic frictional device is broken a drive path of automatic transmission places the neutral gear control gear/unit and (2) the one reset pressure control gear of separated state or slipping state, this reset pressure control gear improves reset pressure one predetermined value of above-mentioned at least one hydraulic frictional device in the neutral gear control procedure of neutral gear control gear, and reduces this reset pressure gradually after neutral gear control is finished.

Use above-mentioned control apparatus, the neutral gear control gear placed the hydraulic frictional device of the drive path that disconnects automatic transmission and separates or slipping state when vehicle stopped.In addition, when this neutral gear control that this hydraulic frictional device is placed slipping state was finished, the reset pressure of the raising predetermined value of this hydraulic frictional device reduced gradually and gets back to neutral gear and control preceding value of establishing.Therefore, after neutral gear control is tight, carry out skidding during starting control at the starting vehicle simultaneously that skids of lock-up clutch, can avoid being used for the drastic change of reset pressure of the control of skidding of lock-up clutch, thereby the control of skidding can carry out smoothly because of the torque ripple that does not suffer to be caused by the reset pressure drastic change.

Description of drawings

From finding out above-mentioned and/or other purpose of the present invention, feature and advantage below in conjunction with accompanying drawing to knowing the explanation of exemplary embodiment, wherein same or analogous element uses same or analogous label.In the accompanying drawing:

Fig. 1 is the schematic representation of an automatic transmission of a vehicle, and this vehicle uses the control apparatus as a lock-up clutch of this vehicle of one embodiment of the invention;

Fig. 2 is the operation table of the gear-change operation of explanatory drawing 1 automatic transmission;

Fig. 3 illustrates that one uses the input and output signal of the electric control device/unit in Fig. 1 embodiment;

Fig. 4 illustrates a hydraulic control circuit in Fig. 1 automatic transmission, definitely says that one is used for the major component of the hydraulic control circuit of lock-up clutch control;

Fig. 5 illustrates the signal pressure P that a linear solenoid valve generates in Fig. 4 hydraulic control circuit _LinAnd the relation between the pressure difference Δ P of lock-up clutch;

Fig. 6 is the functional-block diagram of the major control function of explanation electric control device shown in Figure 3;

The sequential chart of the control of carrying out by Fig. 6 lock-up clutch control apparatus when Fig. 7 is the explanation vehicle launch of skidding;

Fig. 8 illustrates with Fig. 6 one target value of skidding and determines that device/unit determines that the skid prestor of rotational speed N sm of a target concerns;

The sequential chart of first line pressure control of carrying out by Fig. 6 one reset pressure control gear/unit when Fig. 9 finishes for the control of explanation neutral gear;

Figure 10 is for a major component of the control operation of explanation electric control device/unit shown in Figure 3, definitely say the skid flow chart of control program of the lock-up clutch of carrying out when vehicle launch;

Figure 11 is for a major component of the control operation of explanation electric control device shown in Figure 3, definitely say that one finishes the skid flow chart of interrupt routine of control of Figure 10 lock-up clutch;

Figure 12 is for a major component of the control operation of explanation electric control device shown in Figure 3, definitely say that one determines that the lock-up clutch control of skidding finishes the flow chart of the program of condition;

Figure 13 is for a major component of the control operation of explanation electric control device shown in Figure 3, definitely say the flow chart of a reset pressure control program, and in this program, first line pressure is finished in neutral gear control and reduced gradually after tight;

What Figure 14 illustrated the characteristic of Fig. 1 one torque-converters, particularly this torque-converters can hold factor (capacityfactor) C;

Figure 15 is one of explanation another embodiment of the present invention skid flow chart of working condition of control restricting means of control gear and that skids; And

Figure 16 is the sequential chart of explanation Figure 15 working condition.

Embodiment

Describe the present invention's one exemplary embodiment in detail below in conjunction with accompanying drawing.Fig. 1 illustrates a drive system 10 of a vehicle, and this drive system is used the control apparatus of one embodiment of the invention.This is applicable to that the drive system 10 of a FF (front-mounted engine front wheel driving) vehicle comprises an automatic transmission 16 of laterally installing and a motor 12 as the vehicle driving power source.The power that is used as an internal-combustion engine of motor 12 is passed to left and right sidesing driving wheel through one as torque-converters 14, automatic transmission 16, a differential (gear) transmission device (not shown) and a pair of semiaxis of a dydraudynamic drive unit.

Torque-converters 14 comprises a pump impeller 14p who is connected with the bent axle of motor 12, a turbine 14t who is connected with the input shaft 32 of automatic transmission 16 and the guide wheel 14s that is connected with a speed-change gear box shell 36 once an overrunning clutch.Torque-converters 14 uses fluid that the power of motor 12 is passed to automatic transmission 16.Torque-converters 14 also comprises a lock-up clutch 38 between pump impeller 14p and turbine 14t.Lock-up clutch 38 optionally places jointing state, slipping state or separated state by the clutch switching valve 52 and of a hydraulic control circuit 44 control valve 56 that skids.As hereinafter describing in detail, clutch switching valve 52 is used for switching hydraulic fluid and engages grease chamber 18 separates grease chamber 20 with one supply to one of lock-up clutch 38, and skid control valve 56 is used for the joint grease chamber 18 and the pressure difference Δ P that separates between the grease chamber 20 of solenoidoperated cluthes 38.When lock-up clutch 38 was in full jointing state, pump impeller 14p and turbine 14t became an integral body and rotate together.

Automatic transmission 16 comprises that first transmission unit 24 and main 30, the first and second transmission units 24,30, second transmission unit that are made of star-like second planetary gear set 26 of a single file and a pair of planet-shaped the third line star gear train 28 that mainly are made of star-like first planetary gear set 22 of a single file are positioned on the same axle.Automatic transmission 16 is used for changing the output power of the rotating speed and an output gear 34 of input shaft 32.Input shaft 32 can be one by the turbine shaft of a power source as a torque-converters of an engine rotation or driving.Output gear 34 can directly or through a countershaft and a differential gear unit mesh, thereby drives left and right sidesing driving wheel.Be noted that on automatic transmission 16 structures substantial symmetry in its center line (axis), so lower half portion of the not shown center line of Fig. 1.

First planetary gear set 22 of first transmission unit 24 has three rotating components i.e. a central gear S1, a planet carrier CA1 and a gear ring R1.Central gear S1 is connected with input shaft 32 and is subjected to the driving of input shaft 32, gear ring R1 is fixed on the speed-change gear box shell 36 and does not rotate through one the 3rd break B3, thus as the planet carrier CA1 of output member in the middle of power is passed to second transmission unit 30 than input shaft 32 low rotational speed.Second and the third line star gear train 26 of second transmission unit 30 and 28 parts are connected to each other and four rotating component RM1-RM4 are provided.Say that definitely a central gear S3 of the third line star gear train 28 provides the first rotating component RM1, the gear ring R3 of the gear ring R2 of second planetary gear set 26 and the third line star gear train 28 is connected to each other and the second rotating component RM2 is provided.The planet carrier CA3 of the planet carrier CA2 of second planetary gear set 26 and the third line star gear train 28 is connected to each other and the 3rd rotating component RM3 is provided, and the central gear S2 of second planetary gear set 26 provides the 4th rotating component RM4.Second and the third line star gear train 26,28 constitute a Ravigneaux type epicyclic train, wherein, planet carrier CA2 and CA3 are made of a common part, gear ring R2 and R3 are made of a common part, and the planetary pinion of second planetary gear set 26 also is used as second planetary pinion of the third line star gear train 28.

The first rotating component RM1 (central gear S3) can be connected with case shell 36 by the first break B1 and stop operating selectively, and the second rotating component RM2 (gear ring R2, R3) can be connected with case shell 36 by the second break B2 and stop operating selectively.The 4th rotating component RM4 (central gear S2) can be connected with input shaft 32 through first clutch C1 selectively, and the second rotating component RM2 (gear ring R2, R3) can be connected with input shaft 32 through second clutch C2 selectively.The planet carrier CA1 of the first rotating component RM1 (central gear S3) and first planetary gear set 22 fuses as middle output member, the 3rd rotating component RM3 (planet carrier CA2, CA3) and the output gear 34 output rotational power that fuses.The first break B1, the second break B2, the 3rd break B3, first clutch C1 and second clutch C2 are the polydisc type hydraulic frictional device with oil hydraulic cylinder or actuator mechanism frictional engagement.

Fig. 2 operation table illustrates the relation between the working state of each speed change level of automatic transmission 16 and clutch C1, C2 and break B1-B3.In Fig. 2, " O " represents that this rubbing device is in jointing state.The speed ratio of each speed change level is decided by gear ratio ρ 1, ρ 2, the ρ 3 of first planetary gear set 22, second planetary gear set 26 and the third line star gear train 28.For example, as ρ 1 ≈ 0.60, ρ 2 ≈ 0.46, ρ 3 ≈ 0.43, then draw speed ratio shown in Figure 2.At this moment, it is that the value of each speed ratio level (being the ratio of adjacent shelves speed ratio) is suitable that automatic transmission 16 provides suitable speed ratio characteristic, the ratio (speed ratio beam overall) of slowest ratio and minimum speed ratio (3.194/0.574) reaches approximately 5.568 greatly, and reversing speed change level " Rev " has an appropriate speed ratio.Therefore, this embodiment's automatic transmission 16 uses two clutch C1, C2 and three break B1-B3 to establish 6 forward rotational speed and a reversing rotating speed, than the automatic transmission of using three clutches and two breaks, because clutch quantity reduces, so its weight, cost and axial length all reduce.Particularly, star-like second planetary gear set 26 of the single file of second transmission unit 30 and the star-like the third line star of duplicate rows gear train 28 constitute a Ravigneaux type epicyclic train, thereby component number and axial length further reduce.

Fig. 3 illustrates the input and output of electric control device 40 as the automated shift control of the gear shift of a control automatic transmission 16.In Fig. 3, electric control device 40 receives an ON signal from an igniting switch output, one signal from the expression engine speed Ne of engine rotation speed sensor output, one signal from the input shaft rotating speed Nin of the expression secondary speed Nt of transfer input shaft speed sensors output or automatic transmission 16, one signal from the expression engine water temperature Tw of engine water temperature sensor output, one signal from the expression Engine Inlet Temperature Ta of engine air inlet temperature sensor output, one from the signal of the expression closure opening θ th of closure opening sensor output and a signal from the expression accelerating travel θ acc of acceleration stroke sensor output.Electric control device 40 also receives a signal from the expression brake operating of brake switch output, one signal from the expression vehicle velocity V (output shaft rotational speed N out) of vehicle speed sensor output, one signal from the expression shift level lengthwise position of gearshift position sensor output, one signal from the expression shift level lateral attitude that this shift pattern sensor is exported, one signal from the rotational speed N t of the expression turbine 14t of turbine speed sensor output, the signal of the rotational speed N out of the output gear (output shaft) of one expression automatic transmission 16, the signal of the oily temperature Toil of one expression automatic transmission 16, the signal of the operating position of one expression shift mode switch, one signal from the output of ABS electric control device, one signal from the output of VSC/TRC electric control device, one from signal of A/C electric control device output or the like.

Electric control device 40 is one for example to comprise the micro computer of CPU, ROM, RAM and various interface, according to the routine processes input signal that is stored in advance among the ROM, thereby generates various output signals.Output signal can comprise the drive signal of exporting to starter motor, one exports to the fuel jet signal of fuel injector, one exports to a solenoidal signal of an on/off valve of the gear shift control that is used for automatic transmission 16, one exports to the signal of one solenoid/magnetic switch of a linear solenoid valve of the hydraulic control that is used for automatic transmission 16, one exports to the index signal of a shift pattern indicator, one exports to the signal of ABS electric control device, one exports to the signal of VSC/TRC electric control device, one exports to signal of A/C electric control device or the like.

Fig. 4 illustrates a major component, definite the say so relevant part of the Engagement Control with lock-up clutch 38 of hydraulic control circuit 44 of hydraulic control circuit 44 of the gear shift control of the Engagement Control that is used for lock-up clutch 38 and automatic transmission 16.The linear solenoid valve control automatic transmission 16 of the solenoid of the on/off valve of the use gear shift control of the not shown gear shift of Fig. 4 control and hydraulic control is to generate the hydraulic control circuit of a speed ratio in 6 forward rotational speed and the reversing rotating speed.

With reference to figure 4, this hydraulic control circuit 44 comprises valve 50, a clutch switching valve 52, a linear solenoid valve 54 and of the operated by solenoid control valve 56 that skids.The valve 50 of operated by solenoid switches solenoid 49 by one and is manipulated to ON or OFF position and generates a switching signal pressure P sw.Clutch switching valve 52 places the disengaging configuration and of separated state lock-up clutch 38 to be placed between the engagement positio of jointing state according to switching signal pressure P w at a lock-up clutch 38 to switch.Linear solenoid valve 54 generates a signal pressure P who is used to skid control according to the driving current Islu by electric control device 40 supplies _LinThe control signal pressure P of skidding that skid control valve 56 generates according to linear solenoid valve 54 _LinBy regulate to engage grease chamber 18 and separate pressure difference Δ P between the grease chamber 20 and control the amount of skidding of lock-up clutch 38.

As shown in Figure 4, hydraulic control circuit 44 comprises a pump 60, and this pump sucks after collection filter mouthful (strainer) 58 gets back to the hydraulic fluid of a fuel tank (not shown) and pumps high pressure hydraulic fluid.Be adjusted to the first line pressure P11 from the pressure of the high pressure hydraulic fluid of pump 60 output by a decompression type first modulating valve 62.First modulating valve 62 generates basis with the first line pressure P11 of the accelerating travel of the linear solenoid valve SLT output of the control that is subjected to electric control device 40 or the closure pressure raising that the closure opening is directly proportional and through one first Oil of Oil Pipeline passage, 64 these pressure P 11 of output.The first line pressure P11 is as the reset pressure of the activating pressure that is supplied to hydraulic frictional device in the automatic transmission 16 such as clutch C1, C2 and break B1-B3.The first line pressure P11 predetermined value that raises in the neutral gear control procedure, this hands over hereinafter.The second decompression type modulating valve 66 is regulated from the pressure of the hydraulic fluid of first modulating valve, 62 outflows according to closure pressure, thereby generates the second line pressure P12 corresponding with the output torque of motor 12.One the 3rd modulating valve 68 is the reduction valve of one first line pressure P11 as reset pressure, and it generates the 3rd a constant line pressure P13.One manually operated valve 70 generates a R scope pressure P when shift level places R (reversing) scope _ROne OR valve 72 is selected the pressure P of actuated brake B2 _B2With R scope pressure P _RMiddle the higher person generates selected pressure.

Clutch switching valve 52 comprise one with the separating opening 80 that grease chamber 20 is communicated with that separates of lock-up clutch 38, the one joint mouth 82 that is communicated with joint grease chamber 18, the inlet opening 84 of one second line pressure P12, discharging engages first floss hole 86 of the hydraulic fluid in the grease chamber 18 when lock-up clutch 38 separates, discharging separates second floss hole 88 of the hydraulic fluid in the grease chamber 20 and be used for supplying supply port 90 from a part of hydraulic fluid that is used to cool off of second modulating valve, 66 dischargings when lock-up clutch 38 engages when lock-up clutch 38 engages.Clutch switching valve 52 comprises that also a valve rod 92 that switches the connection of these mouthfuls, can be against the plunger 96 of the end adjacent with spring 94 of valve rod 92 to the spring 94 of OFF position bias voltage and this valve rod 92.Clutch switching valve 52 also comprise one be formed between valve rod 92 and the plunger 96, for R scope pressure P _RActing on grease chamber 98, on the opposing end surface of valve rod 92 and plunger 96 receives the grease chamber 100 and that acts on the first line pressure P11 on plunger 96 other ends and receives from the switching signal pressure P of valve 50 outputs of operated by solenoid _SW, make signal pressure P _SWThereby act on and generate the grease chamber 102 that valve 52 is shifted onto the locational thrust of ON on the end face that deviates from spring 94 of valve rod 92.

When the valve 50 of operated by solenoid was in non-excitation/state of activation (OFF state), being communicated with between the grease chamber 102 that a ball valve of valve 50 cuts off clutch switching valve 52 and the OR valve 72, grease chamber 102 was under the emptying pressure at this moment.When the valve 50 of operated by solenoid was in excitation/state of activation (ON state), valve 50 was communicated with grease chamber 102 and OR valve 72, thus the switching signal pressure P _SWAct in the grease chamber 102.That is, when the valve 50 of operated by solenoid is in the OFF state, the switching signal pressure P _SWDo not act in the grease chamber 102, valve rod 92 is at the biasing force of spring 94 and act under the effect of the first line pressure P11 in the grease chamber 100 and be in the OFF position, engages mouth 82 and first floss hole 86 thereby inlet opening 84 interconnects with separating opening 80 and interconnects.Therefore, the hydraulic pressure P in the separation grease chamber 20 of lock-up clutch 38 _OffBring up to and be higher than the hydraulic pressure P that engages in the grease chamber 18 _ON, lock-up clutch 38 separates.Simultaneously, the hydraulic fluid that engages in the grease chamber 18 enters a floss hole through first floss hole 86, an oil cooler 104 and a safety check 106.Have one to prevent the undue reduction valve 108 that increases of pressure between first floss hole 86 and the oil cooler 104.

On the other hand, when the valve 50 of operated by solenoid is in the ON state, the switching signal pressure P _SWAct in the grease chamber 102, valve rod 92 overcomes the biasing force of spring 94 and the first line pressure P11 that acts in the grease chamber 100 is in the ON position, thus inlet opening 84 with engage mouth 82, separating opening 80 and second floss hole 88 and supply port 90 and first floss hole 86 and interconnect respectively.Therefore, the hydraulic pressure P in the joint grease chamber 18 of lock-up clutch 38 _OnBring up to and be higher than the hydraulic pressure P that separates in the grease chamber 20 _Off, lock-up clutch 38 engages.Simultaneously, separate flow through second floss hole 88 and skid control valve 56 of liquid in the grease chamber 20 and enter a floss hole.

Linear solenoid valve 54 is constant the 3rd a line pressure P who is generated by the 3rd modulating valve 68 ₁₃Reduction valve as reset pressure.Linear solenoid valve 54 generates one and accompanys or follow the driving current L of electric control device 40 outputs _SLUThe control signal pressure P of skidding that increases _LinAnd with this control signal pressure P of skidding _LinPass to skid control valve 56.Linear solenoid valve 54 comprises supply port 110, an output that receives the 3rd line pressure P13 control signal pressure P of skidding _LinDelivery outlet 112 and open and close the valve rod 114 of these mouthfuls.Linear solenoid valve 54 also comprise a spring 115, that on the valve closing direction, promotes valve rod 114 use than the little thrust of spring 115 valve open promote valve rod 114 on the direction spring 116, according to driving current I _SLUOpen the control solenoid 118 and that skids that drives valve rod 114 on the direction at valve and receive a feedback pressure (control signal of skidding pressure P _Lin) to be created on the grease chamber 120 that acts on the thrust on the valve rod 114 on the valve closing direction.Valve rod 114 can be on such position, and on this position, solenoid 118 and spring 116 are opened the equilibrium of forces that the power that generates on the direction and spring 115 and feedback pressure generate at valve on the valve closing direction.

Skid control valve 56 comprises that a line pressure mouth 130, that receives the second line pressure P12 receives in the separation grease chamber 20 of lock-up clutch 38 from the receiving port 132 of the hydraulic fluid of second floss hole, 88 dischargings of clutch switching valve 52 and the outfall 134 of the hydraulic fluid that a discharging receiving port 132 receives.Skid control valve 56 also comprise one can the primary importance (position, Fig. 3 middle and lower part) that is communicated with receiving port 132 and outfall 134 with the second place that is communicated with receiving port 132 and line pressure mouth 130 (position, Fig. 3 middle and upper part) thus between mobile valve rod 136 and can push valve rod 136 to the plunger 138 of primary importance against valve rod 136.Skid control valve 56 comprises that also one receives the control signal pressure P of skidding _LinThereby, pressure P _LinAct on plunger 138 and the valve rod 136 to be created on and make the signal pressure grease chamber 140 and that acts on the thrust on plunger 138 and the valve rod 136 on plunger 138 and the direction that valve rod 136 moves apart mutually receive lock-up clutch 38 to separate hydraulic pressure P in the grease chamber 20 _OffThereby, P _OffAct on the grease chamber 142 that with generation plunger 138 and valve rod 136 is pushed to the thrust of primary importance on the plunger 138.Skid control valve 56 comprises that also one receives the hydraulic pressure P in the joint grease chamber 18 of lock-up clutch 38 _OnThereby, hydraulic pressure P _OnAct on the valve rod 136, generate the grease chamber 144 that valve rod 139 is pushed to the thrust of the second place, and a spring 146 of in grease chamber 144, valve rod 136 being pushed to the second place.During skid control valve 56 work, when valve rod 136 is in primary importance, receiving port 132 interconnects with floss hole 134, the hydraulic fluid discharging in the separation grease chamber 20 of lock-up clutch 38, make lock-up clutch 38 joint grease chamber 18 and separate pressure difference Δ P (=P between the grease chamber 20 _On-P _Off) increase.On the other hand, when valve rod 136 was in the second place, receiving port 132 interconnected the second line pressure P with line pressure mouth 130 ₁₂Pass to the separation grease chamber 20 of lock-up clutch 38, make pressure difference Δ P reduce.

Cross-section area is arranged on the plunger 138 is first surface of contact 148 of A1 and its cross-sectional area A 2 than little second surface of contact, 150, the first surface of contact 148 of A1 and second surface of contact 150 with from the grease chamber 142 these order of looking arrange.It is that the 3rd surface of contact 152, its cross-sectional area A 4 of A3 is less than cross-sectional area A 3 and equal the 4th surface of contact 154 of cross-sectional area A 1 of first surface of contact 148 and the 5th surface of contact 156, the three, the 4th and the 5th surface of contact 152,154,156 that its cross-sectional area A 5 equals cross-sectional area A 1 arranged with this order of looking from signal pressure grease chamber 140 that cross-section area is arranged on the valve rod 136.The pass of the cross-section area of these surface of contact be A3＞A1 (=A4=A5)＞A2.Therefore, when clutch switching valve 52 is in the ON position, the control signal of skidding pressure P _LinWhen thereby the less relation that establishes an equation (1) expression down is met, plunger 138 and valve rod 136 contact with each other and become an integral body and move together, and the joint grease chamber 18 of lock-up clutch 38 with separate pressure difference Δ P between the grease chamber 20 with the control signal pressure P of skidding _LinAnd change.This pressure difference Δ P according under establish an equation (2) with the control signal pressure P of skidding relatively _LinLess speed (A3-A2)/A1 and changing.In equation (2), F _sThe biasing force of expression spring 146.

A ₁·P _off≥A ₂·P _lin ...(1)

ΔP＝P _on-P _off＝[(A ₃-A ₂)/A ₁]P _lin-Fs/A ₁ …(2)

As the control signal pressure P of skidding _LinBecome greater than a predetermined value P _A, then the relation by (3) expression that establishes an equation down is met.The value of pre-determining P _A, make the mobility scale Δ P of pressure difference Δ P _SlipEven as big as control that lock-up clutch 38 is skidded, above-mentioned each cross-section area of skid control valve 56 and other size are set for and are made the pass of equation (3) tie up to the control signal pressure P of skidding _LinReach this value P _AIn time, be met.Therefore, when the control signal pressure P of skidding _LinGreater than predetermined value P _AAnd when the relation of equation (3) was met, plunger 138 was separated from each other with valve rod 136, thereby valve rod 136 moves establish an equation under satisfying (4).But, thereby moving under the condition that satisfies equation (4) at valve rod 136, the receiving port 132 and the outfall 134 of skid control valve 56 interconnect the hydraulic pressure P in the separation grease chamber 20 of lock-up clutch 38 _OffFurther drop to barometric pressure.Therefore, pressure difference Δ P becomes and equals Δ P _Max(Δ P=Δ P _Max=P _On), lock-up clutch 38 engages fully.In Fig. 5, solid line is represented the control signal pressure P of skidding relatively by the pressure difference Δ P that causes of operation skid control valve 56 _LinChange.

A ₁·P _off＜A ₂·P _lin …(3)

A ₃·P _lin＝A ₄·P _on+Fs …(4)

As the control signal pressure P of skidding _LinBe reduced to and be equal to or less than the predetermined value P that (5) be met that establishes an equation down thereon _B, then pressure difference Δ P becomes as shown in Figure 5 and equals Δ P _Min(Δ P=Δ P _Min=0), lock-up clutch 38 also separates on the ON position even clutch switching valve 52 is in.

A ₃·P _on＞A ₃·P _lin …(5)

Fig. 6 is the functional-block diagram of the major control function of the above-mentioned electric control device 40 of explanation.In Fig. 6, thereby a shift controller 160 usefulness one prestor gearshift map (not shown) is determined should upgrade still downshift and according to determining that the solenoid that the result drives each gear shift control on/off valve in the hydraulic control circuit 44 drove one or more hydraulic frictional devices to carry out the gear shift of automatic transmission 16 of automatic transmission 16 according to vehicle actual velocity and accelerating travel θ acc or closure opening θ th.

One vehicle launch determines that device 162 determines that vehicles are under the starting conditions, and brake petal was in off working state and accelerating travel θ acc or closure opening θ th and begins to increase from 0 when for example the speed of a motor vehicle was 0.Determine device 162 when vehicle launch and determine that vehicles are in starting conditions following time, the target value of skidding determine device 164 from prestor relation according to actual accelerating travel θ acc or the definite in proper order target of the closure opening θ th rotational speed N of skidding _SM, make engine speed N _eFor example roughly remain unchanged in an initial period as shown in Figure 7, becoming then moves closer to the secondary speed N that increases along with the increase of speed of a motor vehicle N _tOr input shaft rotating speed N _InFor example, the target value of skidding determines that device 164 relation shown in solid line or the dotted line from Fig. 8 determines required output torque according to actual accelerating travel θ acc or closure opening θ th, determines to be used to provide the engine output torque T corresponding with required output torque _eA target engine speed N _EmAnd according to actual secondary speed N _tOr input shaft rotating speed N _InCalculating reaches target engine speed N _EmThe target rotational speed N of skidding _Sm(=N _Em-N _In).Pass shown in the solid line is that closing shown in the dotted line is the optimal fuel economy curve from the optimum operation curve of fuel economy and the consideration of rideability aspect among Fig. 8.

Determine device 162 when vehicle launch and determine that vehicles are in starting conditions following time, a lock-up clutch control apparatus 162 is controlled the valve 50 of the operated by solenoid in the hydraulic control circuit 44 immediately and thereby linear solenoid valve 54 uses the feedback control equation engagement torque of an equation (6) control lock-up clutch 38 as shown below, makes the actual rotational speed N of skidding _s(=N _e-N _In) become and equal the target rotational speed N of skidding _SmIn equation (6), e is the actual rotational speed N of skidding _sWith the target rotational speed N of skidding _SmDeviation, K _PBe proportionality constant, K _IBe integration constant, K _DBe derivative constant, K _FFBe feedforward (feed-forward) constant, first on the right is a feedback term, and second on the right is a feedforward term.

I _SLU＝(K _P·e+K _I·e+K _D·de/dt)+K _FF(f(Te，θth，Nt)) …(6)

The output torque T of motor 12 when vehicle launch _eOnly by torque-converters 14 not local engagement lock-up clutch 38 pass to automatic transmission 16 generally (promptly skidding), engine speed Ne is sharply rising in the initial period shown in the dot and dash line in Fig. 7.Output torque T at motor 12 _eNot only also pass in the present embodiment of automatic transmission 16 by the lock-up clutch 38 of local engagement (promptly skidding) by torque-converters 14, the rising of engine speed Ne (raising) amount is restricted engine speed N _eOriginally roughly remain unchanged as shown in Figure 7, becoming then moves closer to the secondary speed N that increases along with the increase of speed of a motor vehicle N _tAnd along with secondary speed N _tIncrease and increase.Because the control of skidding of lock-up clutch 38 during vehicle launch, torque-converters 14 can't be from the torque capacity big torque that can transmit of motor 12 acceptance than torque-converters 14.That is, lock-up clutch control apparatus 166 carries out the control of skidding of lock-up clutch 38 during vehicle launch, thus prevent torque-converters 14 from motor 12 accept the torque capacity that can transmit than torque-converters 14 be torque-converters 14 can hold the big torque of factor.Although lock-up clutch control apparatus 166 places separated state to lock-up clutch 38 when stopping before vehicle launch, but carry out neutral gear control, reduce to wriggle/creep by disconnecting or roughly disconnect this drive path in the automatic transmission 16 that vehicle launch time-control apparatus 166 can place jointing state to lock-up clutch 38 under the situation of torque (creep-torque) at above-mentioned neutral gear control gear 172, thereby begin the control of skidding rapidly.

When the driving conditions of vehicle becomes a predetermined condition and becomes a condition that is equal to or greater than a predetermined value as one with the merit (work) that engine stall/stop (stall) relevant preset deceleration driving conditions, a predetermined acceleration environment relevant with the deterioration of manoeuvring performance or cornering ability, the lock-up clutch 38 relevant with the working life of lock-up clutch 38 may take place, the control of skidding that 166 pairs of lock-up clutches of control restricting means 168 restriction lock-up clutch control apparatus 38 carry out that one skids.

The preset deceleration driving conditions of this vehicle refers to following condition: more engine stall may take place during the possibility increase vehicle launch of engine stall during vehicle launch.For example, can determine that when at least one condition in the following condition satisfies vehicle is under this preset deceleration condition: (a) retardation of vehicle is equal to or greater than a predetermined value, (b) activate a braking device of this vehicle, (c) rate of descent of the negative change of engine speed Ne or engine speed Ne is equal to or greater than a predetermined value, (d) rate of descent of accelerating travel θ acc or closure opening θ th is equal to or greater than a predetermined value, (e) accelerator pedal is on the off-position, (f) with control relevant sensor such as the vehicle speed sensor of skidding, speed probe or engine rotation speed sensor break down, (g) engine speed Ne becomes the secondary speed Nt that is equal to or less than torque-converters 14, (h) distance of leaving a front vehicles becomes and is equal to or less than a predetermined value, and (i) output shaft rotational speed N out or vehicle velocity V are brought up to and be equal to or greater than a predetermined value.The control restricting means 168 that skids during as the condition of possibility that above-mentioned increase engine stall occurs during vehicle launch stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.

The predetermined acceleration environment of vehicle refers to such condition: maneuverability/maneuverability during vehicle launch (drivability) worsens.For example, can determine that when at least one condition in the following condition satisfies vehicle is under the predetermined acceleration environment: (a) accelerating travel θ acc or closure opening θ th become and are equal to or greater than a predetermined value, (b) increment rate of accelerating travel θ acc or closure opening θ th becomes and is equal to or greater than a predetermined value, (c) vehicle begins to travel on going up a slope or the gradient of going up a slope that vehicle travels thereon becomes and is equal to or greater than a predetermined value one, and the manually-operable gear changing mode of (d) selecting automatic transmission 16.The control restricting means 168 that skids becomes at accelerating travel θ acc or closure opening θ th and reduces to skid the torque capacity of the lock-up clutch 38 under the control when being equal to or greater than predetermined value; When being equal to or greater than predetermined value, the increment rate of accelerating travel θ acc or closure opening θ th stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.Skid and control the torque capacity of restricting means 168 according to the lock-up clutch 38 of grade reduction under the control of skidding of this upward slope; Become in the gradient of this upward slope and to stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when being equal to or greater than predetermined value.When selecting the manually-operable gear changing mode of automatic transmission 16, for example when gear changing mode when an automaitc shfit mode converts the hand shift mode to or when shift level is pushed to from the D position 3,2 and the L position skid during arbitrary position and control the control of skidding that restricting means 168 stops 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.

The merit of lock-up clutch 38 condition that is equal to or greater than predetermined value that becomes refers to such condition: the predetermined condition of determining the state that the friction material of lock-up clutch 38 reduces working life is met.For example, can establish above-mentioned condition when at least one condition in the following condition satisfies: (a) the heat estimated value (or calculated value) that absorbs of lock-up clutch 38 surpasses a predetermined value and/or absorbs heat or its integral value keeps greater than a predetermined value in one period scheduled time or in the longer time, (b) the temperature T oil of the hydraulic fluid in the automatic transmission 16 become be equal to or greater than a predetermined value and (c) when accelerating travel θ acc is in the prespecified range acceleration of vehicle be equal to or less than a predetermined value.The condition that the acceleration of vehicle is equal to or less than a predetermined value when accelerating travel θ acc is in the prespecified range refers to such conditioned disjunction state: though vehicle acceleration that vehicle launch recorded after a period of time or speed of a motor vehicle accelerating travel θ acc be in one be equal to or greater than do not reach in the acceleration range of a predetermined value yet or super only with the accelerating travel θ acc relevant acceleration or the speed of a motor vehicle.When the running resistance height of vehicle, for example vehicle travel on one goes up a slope or thereby this operational vehicle is applied the load of a Parking or emergency braking lock-up clutch 38 or merit because this high running resistance can form this condition when big.Here, the parameter of accelerating travel θ acc as an expression engine loading, it is equivalent to the flow rate, fuel injection amount etc. of closure opening θ th, air inlet.

The heat estimated value (or calculated value) that absorbs (or generation) when lock-up clutch 38 surpasses the control of skidding that the control restricting means 168 that skids when a predetermined value and/or absorption heat or its integral value keep greater than a predetermined value in one period scheduled time or in the longer time also stops 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.In addition, also stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when the become control restricting means 168 that skids when being equal to or greater than this predetermined value of the oily temperature Toil of automatic transmission 16.In addition, the acceleration of vehicle is equal to or less than this predetermined value when being in this prespecified range as accelerating travel θ acc, and the control restricting means 168 that skids also stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.

Get back to Fig. 6, one stop to determine that device 170 for example determines that vehicle is in vehicle stop state when output shaft rotational speed N out or vehicle velocity V are equal to or less than a predetermined parking judgment value.One neutral gear control gear 172 for example stop to determine that device 170 determines that vehicle parkings, accelerating travel θ acc or closure opening θ th equal 0, shift level is in the D position and vehicle is carried out neutral gear control on level road the time and made this drive path of automatic transmission 16 roughly place off state, improves fuel efficiency or reduces the torque of wriggling thereby reduce motor 12 loads during by idling.In neutral gear control, as the clutch C1 of the hydraulic frictional device of establishing the first speed transmission level and break B2 substantial separation (promptly placing the slipping state slightly that engages before tight) and engaging respectively, thereby set up a starting holding state, under this state, this drive path substantial separation or disconnection of automatic transmission 16, but clutch C1 is in case just can start immediately from half joint or slipping state engaged with vehicle.

The input torque Tin that one reset pressure control gear 174 is represented according to common available accelerating travel θ acc or closure opening θ th is through first modulating valve 62 or second modulating valve 66 of linear solenoid valve SLT regulating and controlling as the first line pressure P11 of the reset pressure of each hydraulic frictional device in the automatic transmission 16.When carrying out neutral gear control when neutral gear control gear 172 stops, reset pressure control gear 174 improves the first line pressure P11, one predetermined value as shown in Figure 9, thereby guarantees to be subjected to the controllability of activating pressure of the clutch C1 of neutral gear control.When vehicle lock-up clutch 38 after neutral gear control is finished is in when starting under the slipping state, reset pressure control gear 174 reduces the first line pressure P11 as Fig. 9 dotted line example gradually, linearly with the predetermined variation rate.

Figure 10,11,12 and 13 is the flow chart that the major component of the control operation of being undertaken by electric control device 40 is described.Definitely say, a lock-up clutch control program of carrying out when Figure 10 illustrates vehicle launch, Figure 11 is illustrated in some time lag to determining whether the control of Figure 10 lock-up clutch will finish an interruption/insertion program of carrying out, Figure 12 in some time lag for controlling the interrupt routine that the content of finishing sign is carried out, and Figure 13 illustrates first line pressure (reset pressure) control program of carrying out when the control of Figure 10 lock-up clutch is carried out in a neutral gear control back when finishing.

With reference to Figure 10, after step SA1 carries out the known input/output signal of prior art and handles, determining that with vehicle launch the corresponding step SA2 of device 162 determines whether vehicle starts and determines promptly whether brake petal has got back to off-position.As the answer at step SA2 is not, then repeats above-mentioned steps SA1.As in the answer of step SA2 for being, clutch switching valve 52 switches to the ON position by the valve 50 of operated by solenoid and linear solenoid valve 54 starts skid control valve 56 in step SA3, thereby lock-up clutch 38 is switched to the state of a control of skidding.Determining among the corresponding next step SA4 in device/unit 164 with the target value of skidding, for example relation shown in solid line or the dotted line is determined required output torque according to actual accelerating travel θ acc or closure opening θ th from Fig. 8, determines to be used to provide the engine output torque T corresponding with required output torque _eA target engine speed N _Em, according to actual secondary speed N _tBe actual input shaft rotating speed N _InCalculating is used for reaching target engine speed N _EmThe target rotational speed N of skidding _Sm(=N _Em-N _t).Determine the target rotational speed N of skidding _Sm, make engine speed N in the vehicle launch process _eFor example in an initial period, roughly remain unchanged as shown in Figure 7, move closer to the secondary speed N that increases along with the increase of speed of a motor vehicle N then _tOr input shaft rotating speed N _In

Carry out the step SA5-SA9 corresponding then with lock-up clutch control apparatus 166.Definitely say, in step SA5, determine lock-up clutch 38 the actual rotational speed N s that skids (=Ne-Nin) whether less than the target rotational speed N sm that skids.As in the answer of step SA5 for not, the torque capacity of lock-up clutch 38 in step SA6 (torque is transmitted in institute) re-executes step SA5 thereby increase by one predetermined value reduces to skid behind the rotational speed N s.As in the answer of step SA5 for being, whether the actual rotating speed that skids of then determining lock-up clutch 38 in step SA7 greater than the target rotational speed N sm that skids.As in the answer of step SA7 for not, the torque capacity of lock-up clutch 38 in step SA8 (torque is transmitted in institute) thus reducing predetermined value raising skids and re-executes step SA7 behind the rotational speed N s.As in the answer of step SA7 for being, mean that then the actual rotational speed N s that skids is substantially equal to the target rotational speed N sm that skids.At this moment, keep or continue the current slipping state of lock-up clutch 38 at step SA9.

Figure 11 and 12 with skid control restricting means 168 corresponding.In Figure 11 interrupt routine, sign F is finished in definite control in step SW1 _EContent whether be made as " 1 ".As in the answer of step SW1 for not, continuing to carry out this main program at step SW2 is Figure 10 lock-up clutch control program that skids.But, as in the answer of step SW1 for being, finish this main program at step SW3, the control of skidding of lock-up clutch 38 is finished, lock-up clutch 38 skidding when vehicle launch finished or interrupted like this.

When the program of Figure 12 is used for driving conditions when vehicle and becomes a predetermined condition and become a condition that is equal to or greater than a predetermined value as the merit of a preset deceleration driving conditions relevant with engine stall may take place, a predetermined acceleration environment relevant with the deterioration of maneuverability or the lock-up clutch 38 relevant with the working life of lock-up clutch 38 sign F is finished in this control _EContent be made as " 1 " from " 0 ".In step SW11, determine whether vehicle be in that the possibility of engine stall in the vehicle launch process increases travel/operating conditions under.Definitely say, determine whether at least one condition in the following condition satisfies: (a) retardation of vehicle is equal to or greater than a predetermined value, (b) activate a braking device of this vehicle, (c) rate of descent of the negative change of engine speed Ne or engine speed Ne is equal to or greater than a predetermined value, (d) rate of descent of accelerating travel θ acc or closure opening θ th is equal to or greater than a predetermined value, (e) accelerator pedal is on the off-position, (f) with control relevant sensor such as the vehicle speed sensor of skidding, speed probe or engine rotation speed sensor break down, (g) engine speed Ne becomes the secondary speed Nt that is equal to or less than torque-converters 14, (h) become apart from the distance of a front vehicles and be equal to or less than a predetermined value, and (i) output shaft rotational speed N out or vehicle velocity V are brought up to and be equal to or greater than a predetermined value.As the answer at step SW11 is not, determines at step SW12 whether vehicle is under the driving conditions that maneuverability worsens in the vehicle launch process.Definitely say, determine whether at least one condition in the following condition satisfies: (a) accelerating travel θ acc or closure opening θ th become and are equal to or greater than a predetermined value, (b) increment rate of accelerating travel θ acc or closure opening θ th becomes and is equal to or greater than a predetermined value, (c) vehicle begins to travel on going up a slope or the gradient of going up a slope that vehicle travels thereon becomes and is equal to or greater than a predetermined value one, and the hand shift mode of (d) selecting automatic transmission 16.As in the answer of step SW12 for not, determine at step SW13 whether vehicle is under the condition that reduces in working life of the friction material of lock-up clutch 38.Definitely say, determine that whether at least one condition in the following condition satisfies: (a) the heat estimated value (or calculated value) that absorbs of lock-up clutch 38 surpasses a predetermined value and/or absorbs heat or its integral value keeps greater than a predetermined value in one period scheduled time or in the longer time, (b) the temperature T oil of the hydraulic fluid in the automatic transmission 16 become be equal to or greater than a predetermined value and (c) when accelerating travel θ acc is in the prespecified range acceleration (dV/dt) of vehicle be equal to or less than a predetermined value.

When the answer among the SW11-SW13 is not for the time in steps, sign F is finished in this control in step SW14 _EContent remain " 0 ".But for being, then sign F is finished in this control as the answer in the arbitrary step in above-mentioned steps SW11-SW13 _EContent be made as " 1 ", lock-up clutch 36 in the vehicle launch process skidding control finish.

Figure 13 is corresponding with reset pressure control gear 174.For example whether the neutral gear control of definite neutral gear control gear 172 such as the cancellation (for example loosening the brake) by detecting a brake operating, bend the throttle is finished in step SB1.As in the answer of step SB1 for being that whether lock-up clutch control apparatus 166 in the control of skidding when step SB2 determines vehicle launch.As the answer in step SB2 is not, this EOP end of program.As the answer in step SB2 for being, among the first line pressure P11 such as Fig. 9 from moment t _EShown in the dotted line that stretches out than existing situation shown in the solid line gradually, reduce lentamente.Determine at step SB4 whether the first line pressure P11 has reached original appropriate value then.This appropriate value is the value of establishing in the non-neutral gear control time, and decides according to the prestor control law.As long as the answer in step SB4 is just carried out above-mentioned steps SB2, SB3 and SB4 to keep reducing the first line pressure P11 repeatedly for not.As the answer in step SB4 for being this EOP end of program.

Here, so determine to skid in the joint grease chamber 18 of the pressure difference Δ P that generates lock-up clutch 38 in the control procedure pressure with separate grease chamber 20 in pressure, make the pressure that is higher than in the joint grease chamber 18 that separates the pressure in the grease chamber 20 equal the second line pressure P12, and generate the pressure that separates in the grease chamber 20 with the second line pressure P12 with the skid control valve 56 that hangs down pressure selected in one of drainage pressure or lubricating oil pressure with being communicated with grease chamber 20.Therefore, the control of skidding of lock-up clutch 38 is subjected to the influence and the interference of second line pressure P12 change.In addition, the hydraulic pressure that discharges from first modulating valve 62 of regulating the first line pressure P11 is subjected to the adjusting of second modulating valve 66 and generates the second line pressure P12, and therefore the second line pressure P12 is subjected to the influence of first line pressure P11 change.But, in the present embodiment, the first line pressure P11 after neutral gear control is finished gradually, reduce lentamente, thereby prevent the second line pressure P12 drastic change and second line pressure remained on than under the steady state.Thereby the control of skidding that advantageously prevents lock-up clutch 38 is subjected to the influence as the first line pressure P11 drastic change of reset pressure.

According to present embodiment, lock-up clutch control apparatus 166 is worked when vehicle launch and lock-up clutch 38 is placed slipping state.Therefore, during vehicle launch, from the torque of motor 12 output not only through torque-converters 14, also through lock-up clutch 38 pass to this transmission system after level, thereby suppress the raising of motor 12 rotating speeds, than power only when the existing situation of torque-converters 14 transmission is guaranteed vehicle launch fuel economy be improved.

According to present embodiment, lock-up clutch control apparatus 166 work and lock-up clutch 38 is placed slipping state during vehicle launch, thereby than torque-converters 14 transmit the big torque of torque capacity and do not pass to torque-converters 14 from motor 12.Therefore can prevent the kinetic equation loss that torque-converters 14 can take place when accepting the big torque of torque capacity than torque-converters 14 from motor 12, thereby guarantee further that in the vehicle launch process fuel economy improves.

Control apparatus of the present invention is included in the control restricting means 168 that skids that limits when the vehicle driving condition becomes a predetermined condition or forbid the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.Because this control restricting means 168 that skids is provided, therefore thereby the merit that is in a certain acceleration environment of preset deceleration driving conditions that the engine stall possibility increases or the maneuverability that influences vehicle or lock-up clutch 38 when vehicle becomes and is equal to or greater than condition following time that a predetermined value influences the working life of lock-up clutch 38, limits for example to stop to skid of lock-up clutch 38 in the vehicle launch process.Therefore, the control apparatus of present embodiment is guaranteed enough height and guarantee the long enough in working life of lock-up clutch 38 of ability that the possibility of the engine stall of vehicle reduces, guarantees maneuverability or starting and acceleration.

According to this embodiment, the control restricting means 168 that skids is determining that vehicle stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when being in a Reduced Speed Now state, thereby the possibility of guaranteeing the engine stall of vehicle reduces, and promptly makes vehicle less engine stall may take place.

According to this embodiment, the control restricting means 168 that skids stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when all conditions of a predefined conditioned disjunction of the travelling state that is used for determining that the engine stall possibility increases are met, thereby the possibility reduction of guaranteeing the engine stall of vehicle promptly makes vehicle less engine stall may take place.

According to this embodiment, skid and stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when control restricting means 168 at least one condition in following condition is met: (a) retardation of vehicle is equal to or greater than a predetermined value, (b) activate a braking device of this vehicle, (c) the negative change of engine speed Ne is equal to or greater than a predetermined value, (d) rate of descent of accelerating travel θ acc or closure opening θ th is equal to or greater than predetermined value, (e) accelerator pedal is on the off-position, (f) with control relevant sensor such as the vehicle speed sensor of skidding, speed probe or engine rotation speed sensor break down, (g) engine speed Ne becomes the secondary speed Nt that is equal to or less than torque-converters 14, (h) become apart from the distance of a front vehicles and be equal to or less than predetermined value, and (i) output shaft rotational speed N out brings up to and is equal to or greater than predetermined value.Stop when this class condition that increases the engine stall possibility is met owing to skidding of lock-up clutch 38 is controlled at, so motor less may produce engine stall.

According to present embodiment, the control restricting means 168 that skids limits, for example stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when detecting a certain acceleration environment of vehicle, thereby maneuverability/ride quality (ability of promptly starting and quickening) of guaranteeing vehicle is enough high.

According to present embodiment, the control restricting means 168 that skids is determining that vehicle is in the lockmaking of following time limit of condition that makes the maneuverability of vehicle worsen and ends the control of skidding of 166 pairs of lock-up clutches 38 of clutch control device, thus the enough height of the maneuverability (ability of promptly starting and quickening) of guaranteeing vehicle.

According to present embodiment, the control restricting means 168 that skids becomes at accelerating travel θ acc or closure opening θ th and reduces to be in the torque capacity of the lock-up clutch 38 under the slipping state when being equal to or greater than predetermined value; Become in the increment rate of accelerating travel θ acc or closure opening θ th and to stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when being equal to or greater than predetermined value.The torque capacity of the lock-up clutch 38 of grade reduction under slipping state of the upward slope that the control restricting means 168 that skids also travels thereon according to vehicle; Become in the gradient of this upward slope and to stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when being equal to or greater than predetermined value.The control restricting means 168 that skids also stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when selecting the hand shift mode of automatic transmission 16.Therefore, this embodiment's control apparatus stops the control of skidding to lock-up clutch 38 when a condition that makes the maneuverability of vehicle worsen is met, thereby guarantees the starting and the accelerating ability height of vehicle.

According to present embodiment, the control restricting means 168 that skids becomes in the merit of lock-up clutch 38 and stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when being equal to or greater than predetermined value, thus the enough height of the maneuverability (ability of promptly starting and quickening) of guaranteeing vehicle.

According to present embodiment, stop the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus during pre-conditioned being met of the working state that the control restricting means 168 that skids reduced in the working life of the friction material that is used for determining lock-up clutch 38, thereby the working life of guaranteeing lock-up clutch 38 is enough high.

According to present embodiment, the control restricting means 168 that skids is estimated the caloric receptivity of lock-up clutch 38 and is surpassed the control of skidding that stops 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when predetermined value and/or caloric receptivity or its integral value keep greater than predetermined value in one period scheduled time or in the longer time in this caloric receptivity estimated value.The control restricting means 168 that skids also stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus when the temperature T oil of the hydraulic fluid of automatic transmission 16 is equal to or greater than predetermined value.In addition, the acceleration (dV/dt) of vehicle is equal to or less than predetermined value when being in the prespecified range as accelerating travel θ acc, and the control restricting means 168 that skids also stops the control of skidding of 166 pairs of lock-up clutches 38 of lock-up clutch control apparatus.Therefore, the control apparatus of present embodiment is guaranteed the long enough in working life of lock-up clutch 38.

The control apparatus of present embodiment comprises the automatic transmission 16 that (a) is connected with the outlet side effect of the torque-converters 14 that lock-up clutch 38 is housed, (b) during vehicle parking cut-off clutch C1 (hydraulic frictional device) to disconnect the neutral gear control gear 172 of drive path in the automatic transmission 16, and (c) in the neutral gear control procedure, raise as clutch C1, the reset pressure control gear 174 of a predetermined value of the first line pressure P11 of the reset pressure of break B2 etc., under neutral gear control, neutral gear control gear 172 is controlled to disconnect the drive path of automatic transmission 16, reduces reset pressure when finishing as shown in phantom in Figure 9 gradually in this disconnection control or neutral gear control then.Here, the control hydraulic pressure that is used for controlling lock-up clutch 38 is regulated from the reset pressure that is subjected to 174 controls of reset pressure control gear.Therefore, when the lock-up clutch 38 of torque-converters 14 is subjected to the control of lock-up clutch control apparatus 166 during at the tight back of gear shift control vehicle launch and when being in slipping state, can prevent to be used for the drastic change of reset pressure of the control of skidding of lock-up clutch 38, thereby advantageously eliminate of the interference of this drastic change of reset pressure the control of skidding.

The following describes another embodiment of the present invention.In the following description, represent with same label, repeat no more with parts or part identical among the embodiment of front.

Figure 15 is the flow chart of the control operation of the explanation lock-up clutch control apparatus 166 and the control restricting means 168 that skids.Say that definitely restriction was skidded control to prevent or to suppress a control procedure of friction material reduction in working life when Figure 15 flow chart described vehicle launch in detail.In control program shown in Figure 15, act in the process of lock-up clutch being controlled with local engagement lock-up clutch 38 during as vehicle launch that load on the lock-up clutch 38 is excessive then to stop skidding control.Figure 16 is the sequential chart of the control operation of explanation Figure 15.

Referring to Figure 15 and 16, as moment t in Figure 16 ₀When bend the throttle begins accelerating vehicle, carry out the step SC1 corresponding and when vehicle launch, respond this accelerations operation beginning lock-up clutch and control as above-mentioned local engagement lock-up clutch 38 shown in Figure 10 with lock-up clutch control apparatus 166.The control of beginning lock-up clutch is that local engagement lock-up clutch 38 occurs in moment t among Figure 16 ₁Then, carry out and the corresponding step SC2-SC4 of control restricting means 168 that skids.In step SC2, whether some precondition that the control of determining to be used for to determine to skid stops is met.For example when vehicle is in acceleration mode and its accelerating travel θ acc and is equal to or greater than a predetermined value; When the oily temperature that is in the coolant temperature of motor 12 and/or automatic transmission 16 when vehicle is equal to or greater than the preheat mode of predetermined value with when mechanical part such as speed probe, temperature transducer and control valve do not break down and can determine that these preconditions are met when unusual.As the answer in step SC2 is not, this EOP end of program.As the answer in step SC2 for being then in step SC3, to determine at moment t ₁Whether the acceleration (dV/dt) of the vehicle that records behind the actual starting of the vehicle scheduled time T is equal to or less than a predetermined decision content α.In Figure 16, t ₂The expression moment of vehicle launch after time T.Because the acceleration (dV/dt) of the vehicle that records after the time T is a value that the vehicle velocity V that records draws divided by time T, can determine in step SC3 therefore whether the vehicle velocity V that records after the time T is equal to or less than predetermined decision content Va after time T.

As the answer in step SC3 is not, this EOP end of program.For being, then vehicle is in by excessive the acting under the excessive working state of friction load on the lock-up clutch 38 of causing of vehicle driving resistance as the answer in step SC3.At this moment, execution in step SC4 terminates in the lock-up clutch control that step SC1 begins, thereby descends the working life that prevents lock-up clutch 38.

In the present embodiment, the merit of determining lock-up clutch 38 behind a period of time T when acceleration of the vehicle that this control apparatus records (dV/dt) or vehicle velocity V are equal to or less than decision content α or Va is equal to or greater than a predetermined value, thereby the lock-up clutch of carrying out when determining to terminate in vehicle launch control, thereby be improved the working life of guaranteeing lock-up clutch 38 according to this.

Although more than be described with reference to the accompanying drawings some exemplary embodiments of the present invention, should see that the present invention is not subjected to the restriction of the details of illustrated embodiment, but other embodiment can be arranged.

In the embodiment shown, according to above-mentioned governing equation (6) the actual rotational speed N s that skids of lock-up clutch 38 is controlled to and equals in the vehicle launch process target that order the calculates rotational speed N sm that skids.But, also can use than the simpler control example of above-mentioned control at the fixed time, to keep the predetermined pressure difference Δ P or the rotational speed N s that skids to make that in the vehicle launch process lock-up clutch 38 skids.In a word, if when vehicle launch not only by torque-converters 14, also by lock-up clutch 38 the input shaft 32 that the output torque Te of motor 12 passes to automatic transmission 16, can carry out the control of skidding of lock-up clutch 38 by any way.

In the embodiment shown, the feedback control of carrying out closed loop with governing equation (6) is controlled to the actual rotational speed N s that skids of lock-up clutch 38 and equals order is calculated in the vehicle launch process the target rotational speed N sm that skids.But available open loop control substitutes this closed loop control, thereby skids control to obtain the target rotational speed N sm that skids according to the value of prestor figure.

In the embodiment shown, according to the actual rotational speed N s that skids of governing equation (6) control lock-up clutch 38, make the rotational speed N s that skids become and equal order is calculated in the vehicle launch process the target rotational speed N sm that skids.But the pressure difference Δ P of skid the rotational speed N s or the lock-up clutch 38 of may command lock-up clutch 38 makes actual engine speed Ne become and equals the target engine speed Nem that order is calculated.

In the embodiment shown, according to the actual rotational speed N s that skids of governing equation (6) control lock-up clutch 38, make the rotational speed N s that skids become and equal order is calculated in the vehicle launch process the target rotational speed N sm that skids.But, can hold factor C (* 10 according to torque-converters 14 from prestor shown in Figure 14 relation for example ^-6Nn/rpm ²) determine an object transmission torque, make this object transmission torque equal by holding torque capacity that factor C represents or than the little predetermined value of this torque capacity, the rotational speed N s that skids of may command lock-up clutch 38 is the pressure difference Δ P of lock-up clutch 38 then, makes the actual transmissions torque of torque-converters 14 equal this object transmission torque.

Although in the embodiment shown torque-converters 14 is used as a dydraudynamic drive unit, can not comprise that the fluid coupling of guide wheel 14s is as this dydraudynamic drive unit to one yet.

Although some embodiments of the present invention more than have been described, should see that the present invention is not subjected to the restriction of the details of illustrated embodiment, but those of ordinary skills can make all changes, correction and improvement to it within the spirit and scope of the present invention.

Claims

1, a kind of control apparatus of a lock-up clutch (38) of control one vehicle, this vehicle has one the dydraudynamic drive unit (14) of this lock-up clutch (38) is housed, this dydraudynamic drive unit (14) is arranged on the outlet side of a motor (12) of this vehicle, it is characterized in that comprising:

During described vehicle launch this lock-up clutch (38) is placed the lock-up clutch control apparatus (166) of slipping state.

2, by the described control apparatus of claim 1, it is characterized in that, this lock-up clutch control apparatus (166) places slipping state to lock-up clutch (38) when vehicle launch, thereby prevents that dydraudynamic drive unit (14) is from the torque capacity big torque of motor (12) acceptance than dydraudynamic drive unit (14).

By the described control apparatus of claim 1, it is characterized in that 3, the driving conditions that also is included in vehicle becomes a predetermined condition time limit lockmaking and ends the skid control restricting means (168) of clutch control device (166) to the control of skidding of lock-up clutch (38).

By the described control apparatus of claim 3, it is characterized in that 4, the control restricting means (168) that skids stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when vehicle is in the Reduced Speed Now condition.

5, by the described control apparatus of claim 3, it is characterized in that the control restricting means (168) that skids stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when predefined at least one condition of the vehicle operation state that is used for determining that the engine stall possibility increases is met.

6, by claim 4 or 5 described control apparatuss, it is characterized in that, skid and stop the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when control restricting means (168) at least one condition in following condition is met: (a) retardation of vehicle is equal to or greater than a predetermined value, (b) activate a braking device of this vehicle, (c) the negative change of engine speed is equal to or greater than a predetermined value, (d) rate of descent of accelerating travel is equal to or greater than a predetermined value, (e) accelerator pedal is on the off-position, (f) detect vehicle speed sensor, at least one sensor breaks down in speed probe and the engine rotation speed sensor, (g) engine speed becomes the secondary speed that is equal to or less than dydraudynamic drive unit (14), (h) become apart from the distance of a front vehicles and be equal to or less than a predetermined value, and (i) speed of a motor vehicle is brought up to and is equal to or greater than a predetermined value.

By the described control apparatus of claim 3, it is characterized in that 7, the control restricting means (168) that skids is in predetermined acceleration environment time limit lockmaking at vehicle and ends the skid control of clutch control device (166) to lock-up clutch (38).

By the described control apparatus of claim 3, it is characterized in that 8, the control restricting means (168) that skids ends the skid control of clutch control device (166) to lock-up clutch (38) in the working state time limit lockmaking that vehicle is in the maneuverability deterioration of vehicle.

9,, it is characterized in that the control restricting means (168) that skids becomes in accelerating travel and reduces to be in the torque capacity of the lock-up clutch (38) under the slipping state when being equal to or greater than a predetermined value by claim 7 or 8 described control apparatuss; Become in the increment rate of accelerating travel and to stop the to skid control of lock-up clutch control apparatus (166) when being equal to or greater than a predetermined value lock-up clutch (38); The torque capacity of the lock-up clutch (38) of grade reduction under slipping state of the upward slope that travels thereon according to vehicle; Become in the gradient of this upward slope and to stop the to skid control of lock-up clutch control apparatus when being equal to or greater than a predetermined value lock-up clutch; Or stop the to skid control of lock-up clutch control apparatus (166) during the hand shift mode of the speed ratio of the automatic transmission (16) on select changing the dydraudynamic drive unit outlet side to lock-up clutch (38).

10, by the described control apparatus of claim 3, it is characterized in that the control restricting means (168) that skids becomes in the merit of lock-up clutch (38) and stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when being equal to or greater than a predetermined value.

11, by the described control apparatus of claim 3, it is characterized in that predefined at least one condition of the working state that the control restricting means (168) that skids reduced in the working life of the friction material that is used for determining lock-up clutch (38) stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when being met.

12, by claim 10 or 11 described control apparatuss, it is characterized in that, the control restricting means (168) that skids is estimated to stop the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when the caloric receptivity of lock-up clutch (38) and at least one condition in following condition are met: (a) this caloric receptivity estimated value surpasses a predetermined value, and (b) caloric receptivity or its integral value in one period scheduled time or for more time maintenance greater than predetermined value; Or the oily temperature of the automatic transmission in vehicle (16) stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38) when being equal to or greater than a predetermined value; Perhaps, the acceleration of vehicle is equal to or less than a predetermined value when being in the prespecified range as accelerating travel, then stops the to skid control of lock-up clutch control apparatus (166) to lock-up clutch (38).

13, by the described control apparatus of claim 1, it is characterized in that this vehicle also comprises an automatic transmission (16) that is operatively connected with the outlet side that the dydraudynamic drive unit (14) of lock-up clutch (38) is housed, this control apparatus further comprises:

Be used for separating basically the neutral gear control gear (172) of a hydraulic frictional device during vehicle parking with the drive path of disconnection automatic transmission (16), and

In the control procedure of the drive path of the disconnection automatic transmission (16) of neutral gear control gear (172), raise this hydraulic frictional device reset pressure one predetermined value and after this separating controlling of neutral gear control gear (172) is finished, reduce the reset pressure control gear (174) of reset pressure gradually

Wherein, be subjected to the reset pressure of reset pressure control gear (174) control to generate the control hydraulic pressure that lock-up clutch control apparatus (166) is used for controlling lock-up clutch (38) by adjusting.

14, a kind of control apparatus of a lock-up clutch of control one vehicle, this vehicle comprises that (a) is equipped with direct coupling one input rotating component and the dydraudynamic drive unit (14) of the lock-up clutch (38) of an output rotating component and (b) one is operatively connected with this outlet side that dydraudynamic drive unit (14) of this lock-up clutch (38) is housed and the automatic transmission that one in a plurality of speed change levels are selected the speed change level is established in the combination of the working state by changing a plurality of hydraulic frictional devices, is characterized in that comprising:

One places at least one hydraulic frictional device of a drive path that disconnects automatic transmission (16) the neutral gear control gear of separated state or slipping state when vehicle parking, and

In the neutral gear control procedure of neutral gear control gear (172), improve reset pressure one predetermined value of described at least one hydraulic frictional device and after neutral gear control is finished, reduce the reset pressure control gear (174) of this reset pressure gradually.

15, a kind of method of a lock-up clutch of control one vehicle, this vehicle has one the dydraudynamic drive unit (14) of this lock-up clutch (38) is housed, and this dydraudynamic drive unit (14) is arranged on the outlet side of the motor (12) of this vehicle, it is characterized in that comprising:

When vehicle launch, carry out this lock-up clutch (38) is placed the control of skidding of slipping state.

16, by the described method of claim 15, it is characterized in that, when vehicle launch, lock-up clutch is placed slipping state, thereby prevent that dydraudynamic drive unit (14) is from the torque capacity big torque of motor (12) acceptance than dydraudynamic drive unit (14).

By the described method of claim 15, it is characterized in that 17, restriction is to the control of skidding of lock-up clutch (38) when the driving conditions of vehicle becomes a predetermined condition.

18, by the described method of claim 17, it is characterized in that, when vehicle is in the Reduced Speed Now condition, stop the control of skidding lock-up clutch (38).

19, by the described method of claim 17, it is characterized in that, when predefined at least one condition of the vehicle operation state that is used for determining that the engine stall possibility increases is met, stop the control of skidding lock-up clutch (38).

20, by claim 18 or 19 described methods, it is characterized in that, at least one condition in following condition stops the control of skidding to lock-up clutch (38) when being met: (a) retardation of vehicle is equal to or greater than a predetermined value, (b) activate a braking device of this vehicle, (c) the negative change of engine speed is equal to or greater than a predetermined value, (d) rate of descent of accelerating travel is equal to or greater than a predetermined value, (e) accelerator pedal is on the off-position, (f) detect vehicle speed sensor, at least one sensor breaks down in speed probe and the engine rotation speed sensor, (g) engine speed becomes the secondary speed that is equal to or less than dydraudynamic drive unit (14), (h) become apart from the distance of a front vehicles and be equal to or less than a predetermined value, and (i) speed of a motor vehicle is brought up to and is equal to or greater than a predetermined value.

21,, it is characterized in that restriction is to the control of skidding of lock-up clutch (38) when vehicle is in a predetermined acceleration environment by the described method of claim 17.

22,, it is characterized in that restriction is to the control of skidding of lock-up clutch (38) when vehicle is in the working state that the maneuverability of vehicle worsens by the described method of claim 17.

23,, it is characterized in that becoming in accelerating travel reduces to be in the torque capacity of the lock-up clutch (38) under the slipping state when being equal to or greater than a predetermined value by claim 21 or 22 described methods; Or become in the increment rate of accelerating travel and to stop the control of skidding when being equal to or greater than a predetermined value lock-up clutch (38); Or the torque capacity of the lock-up clutch (38) of grade reduction under slipping state of the upward slope that travels thereon according to vehicle; Or become in the gradient of this upward slope and to stop the control of skidding when being equal to or greater than a predetermined value lock-up clutch; Or stop the control of skidding during the hand shift mode of the speed ratio of the automatic transmission (16) on select changing dydraudynamic drive unit (14) outlet side to lock-up clutch (38).

24,, it is characterized in that becoming in the merit of lock-up clutch (38) stops the control of skidding to lock-up clutch (38) when being equal to or greater than a predetermined value by the described method of claim 17.

25, by the described method of claim 17, it is characterized in that predefined at least one condition of the working state that reduces in the working life of the friction material that is used for determining lock-up clutch (38) stops the control of skidding to lock-up clutch (38) when being met.

26, by claim 24 or 25 described methods, it is characterized in that, estimate that the caloric receptivity of lock-up clutch (38) and at least one condition in following condition stop the control of skidding to lock-up clutch (38) when being met: (a) this caloric receptivity estimated value surpasses a predetermined value, and (b) caloric receptivity or its integral value in one period scheduled time or for more time maintenance greater than predetermined value; Or the oily temperature of the automatic transmission in vehicle (16) stops the control of skidding to lock-up clutch (38) when being equal to or greater than a predetermined value; Perhaps, the acceleration of vehicle is equal to or less than a predetermined value when being in the prespecified range as accelerating travel, then stops the control of skidding to lock-up clutch (38).

27, by the described method of claim 15, it is characterized in that:

This vehicle also comprises an automatic transmission (16) that is operatively connected with the outlet side that the dydraudynamic drive unit (14) of lock-up clutch (38) is housed;

The one hydraulic frictional device that is used for disconnecting the drive path of automatic transmission (16) separates under neutral gear control substantially during vehicle parking;

Reset pressure one predetermined value of this hydraulic frictional device that raises in the neutral gear control procedure of the drive path that disconnects automatic transmission (16) also reduces reset pressure gradually after this neutral gear control is finished; And

By regulating the control hydraulic pressure that reset pressure generates the control of skidding that is used for lock-up clutch (38).

28, a kind of method of a lock-up clutch of control one vehicle, this vehicle comprises that (a) is equipped with direct coupling one input rotating component and the dydraudynamic drive unit (14) of the lock-up clutch (38) of an output rotating component and (b) one is operatively connected with this outlet side that dydraudynamic drive unit (14) of this lock-up clutch (38) is housed and the automatic transmission that one in a plurality of speed change levels are selected the speed change level is established in the combination of the working state by changing a plurality of hydraulic frictional devices, is characterized in that comprising the following steps:

One carries out neutral gear control when vehicle parking places separated state or slipping state at least one hydraulic frictional device that the hydraulic frictional device breaks a drive path of automatic transmission (16), and

In the neutral gear control procedure, improve reset pressure one predetermined value of described at least one hydraulic frictional device and after neutral gear control is finished, reduce this reset pressure gradually.